NVIDIA GeForce 840M vs NVIDIA GeForce GT 640 Rev. 2

Comparative analysis of NVIDIA GeForce 840M and NVIDIA GeForce GT 640 Rev. 2 videocards for all known characteristics in the following categories: Essentials, Technical info, Video outputs and ports, Compatibility, dimensions and requirements, API support, Memory, Technologies. Benchmark videocards performance analysis: PassMark - G3D Mark, PassMark - G2D Mark, Geekbench - OpenCL, CompuBench 1.5 Desktop - Face Detection (mPixels/s), CompuBench 1.5 Desktop - Ocean Surface Simulation (Frames/s), CompuBench 1.5 Desktop - T-Rex (Frames/s), CompuBench 1.5 Desktop - Video Composition (Frames/s), CompuBench 1.5 Desktop - Bitcoin Mining (mHash/s), GFXBench 4.0 - Car Chase Offscreen (Frames), GFXBench 4.0 - Manhattan (Frames), GFXBench 4.0 - T-Rex (Frames), GFXBench 4.0 - Car Chase Offscreen (Fps), GFXBench 4.0 - Manhattan (Fps), GFXBench 4.0 - T-Rex (Fps), 3DMark Fire Strike - Graphics Score.

NVIDIA GeForce 840M

NVIDIA GeForce GT 640 Rev. 2

Differences

Reasons to consider the NVIDIA GeForce 840M

Videocard is newer: launch date 9 month(s) later
Around 7% higher texture fill rate: 17.98 GTexel / s vs 16.74 GTexel / s
Around 7% better floating-point performance: 863.2 gflops vs 803.3 gflops
Around 48% lower typical power consumption: 33 Watt vs 49 Watt
4x more maximum memory size: 4 GB vs 1 GB
2.2x better performance in CompuBench 1.5 Desktop - Face Detection (mPixels/s): 22.848 vs 10.475
38.7x better performance in CompuBench 1.5 Desktop - T-Rex (Frames/s): 1.237 vs 0.032
2.4x better performance in CompuBench 1.5 Desktop - Video Composition (Frames/s): 21.15 vs 8.717
9.1x better performance in CompuBench 1.5 Desktop - Bitcoin Mining (mHash/s): 95.545 vs 10.454

Specifications (specs)
Launch date	12 March 2014 vs 29 May 2013
Texture fill rate	17.98 GTexel / s vs 16.74 GTexel / s
Floating-point performance	863.2 gflops vs 803.3 gflops
Thermal Design Power (TDP)	33 Watt vs 49 Watt
Maximum memory size	4 GB vs 1 GB
Benchmarks
CompuBench 1.5 Desktop - Face Detection (mPixels/s)	22.848 vs 10.475
CompuBench 1.5 Desktop - T-Rex (Frames/s)	1.237 vs 0.032
CompuBench 1.5 Desktop - Video Composition (Frames/s)	21.15 vs 8.717
CompuBench 1.5 Desktop - Bitcoin Mining (mHash/s)	95.545 vs 10.454

Reasons to consider the NVIDIA GeForce GT 640 Rev. 2

Around 2% higher core clock speed: 1046 MHz vs 1029 MHz
2.5x more memory clock speed: 5008 MHz vs 2002 MHz
Around 7% better performance in CompuBench 1.5 Desktop - Ocean Surface Simulation (Frames/s): 173.537 vs 162.594
Around 11% better performance in GFXBench 4.0 - Car Chase Offscreen (Frames): 2309 vs 2085
Around 23% better performance in GFXBench 4.0 - Manhattan (Frames): 3354 vs 2736
Around 1% better performance in GFXBench 4.0 - T-Rex (Frames): 3220 vs 3191
Around 11% better performance in GFXBench 4.0 - Car Chase Offscreen (Fps): 2309 vs 2085
Around 23% better performance in GFXBench 4.0 - Manhattan (Fps): 3354 vs 2736
Around 1% better performance in GFXBench 4.0 - T-Rex (Fps): 3220 vs 3191

Specifications (specs)
Core clock speed	1046 MHz vs 1029 MHz
Memory clock speed	5008 MHz vs 2002 MHz
Benchmarks
CompuBench 1.5 Desktop - Ocean Surface Simulation (Frames/s)	173.537 vs 162.594
GFXBench 4.0 - Car Chase Offscreen (Frames)	2309 vs 2085
GFXBench 4.0 - Manhattan (Frames)	3354 vs 2736
GFXBench 4.0 - T-Rex (Frames)	3220 vs 3191
GFXBench 4.0 - Car Chase Offscreen (Fps)	2309 vs 2085
GFXBench 4.0 - Manhattan (Fps)	3354 vs 2736
GFXBench 4.0 - T-Rex (Fps)	3220 vs 3191

Compare benchmarks

GPU 1: NVIDIA GeForce 840M
GPU 2: NVIDIA GeForce GT 640 Rev. 2

CompuBench 1.5 Desktop - Face Detection (mPixels/s)

GPU 1

GPU 2

22.848

10.475

CompuBench 1.5 Desktop - Ocean Surface Simulation (Frames/s)

GPU 1

GPU 2

162.594

173.537

CompuBench 1.5 Desktop - T-Rex (Frames/s)

GPU 1

GPU 2

1.237

0.032

CompuBench 1.5 Desktop - Video Composition (Frames/s)

GPU 1

GPU 2

21.15

8.717

CompuBench 1.5 Desktop - Bitcoin Mining (mHash/s)

GPU 1

GPU 2

95.545

10.454

GFXBench 4.0 - Car Chase Offscreen (Frames)

GPU 1

GPU 2

2085

2309

GFXBench 4.0 - Manhattan (Frames)

GPU 1

GPU 2

2736

3354

GFXBench 4.0 - T-Rex (Frames)

GPU 1

GPU 2

3191

3220

GFXBench 4.0 - Car Chase Offscreen (Fps)

GPU 1

GPU 2

2085

2309

GFXBench 4.0 - Manhattan (Fps)

GPU 1

GPU 2

2736

3354

GFXBench 4.0 - T-Rex (Fps)

GPU 1

GPU 2

3191

3220

Name	NVIDIA GeForce 840M	NVIDIA GeForce GT 640 Rev. 2
PassMark - G3D Mark	1092
PassMark - G2D Mark	150
Geekbench - OpenCL	5738
CompuBench 1.5 Desktop - Face Detection (mPixels/s)	22.848	10.475
CompuBench 1.5 Desktop - Ocean Surface Simulation (Frames/s)	162.594	173.537
CompuBench 1.5 Desktop - T-Rex (Frames/s)	1.237	0.032
CompuBench 1.5 Desktop - Video Composition (Frames/s)	21.15	8.717
CompuBench 1.5 Desktop - Bitcoin Mining (mHash/s)	95.545	10.454
GFXBench 4.0 - Car Chase Offscreen (Frames)	2085	2309
GFXBench 4.0 - Manhattan (Frames)	2736	3354
GFXBench 4.0 - T-Rex (Frames)	3191	3220
GFXBench 4.0 - Car Chase Offscreen (Fps)	2085	2309
GFXBench 4.0 - Manhattan (Fps)	2736	3354
GFXBench 4.0 - T-Rex (Fps)	3191	3220
3DMark Fire Strike - Graphics Score	503

Compare specifications (specs)

	NVIDIA GeForce 840M	NVIDIA GeForce GT 640 Rev. 2
Essentials
Architecture	Maxwell	Kepler 2.0
Code name	GM108	GK208
Launch date	12 March 2014	29 May 2013
Place in performance rating	1273	1275
Type	Laptop	Desktop
Launch price (MSRP)		$89
Technical info
Boost clock speed	1124 MHz
Core clock speed	1029 MHz	1046 MHz
Floating-point performance	863.2 gflops	803.3 gflops
Manufacturing process technology	28 nm	28 nm
Pipelines	384	384
Texture fill rate	17.98 GTexel / s	16.74 GTexel / s
Thermal Design Power (TDP)	33 Watt	49 Watt
Video outputs and ports
Display Connectors	No outputs	1x DVI, 1x HDMI, 1x VGA
Compatibility, dimensions and requirements
Bus support	PCI Express 2.0, PCI Express 3.0
Interface	PCIe 3.0 x8	PCIe 2.0 x8
Laptop size	medium sized
Length		145 mm
Supplementary power connectors		None
API support
DirectX	12.0 (11_0)	12.0 (11_0)
OpenGL	4.5	4.6
Memory
Maximum RAM amount	4 GB	1 GB
Memory bandwidth	16.02 GB / s	40.06 GB / s
Memory bus width	64 Bit	64 Bit
Memory clock speed	2002 MHz	5008 MHz
Memory type	DDR3	GDDR5
Shared memory	0
Technologies
CUDA
GameWorks
GeForce Experience
GPU Boost
Optimus